A vehicle door lock device in the related art is known which includes a lock mechanism that sets engagement between a vehicle door side latch mechanism and a vehicle body side striker to a releasable unlock state or an unreleasable lock state. For example, JP 2008-248591A (Reference 1) discloses one of the door lock devices of this type. The door lock device (hereinafter, also referred to as a “device in the related art”) includes an actuator that rotates a wheel gear (rotating member) by a drive force of a motor, and an active lever (operating lever) that is turned between an unlock position at which the latch mechanism is set to the unlock state during operation of the actuator and a lock position at which the latch mechanism is set to the lock state. In the door lock device, during rotation of the wheel gear, the active lever is rotated while being engaged with the wheel gear via a protrusion of the wheel gear, and comes into contact with a stopper of a housing at each of the unlock position and the lock position such that the rotation of the active lever is limited.
There is demand for reducing operation noise of the door lock device, which is induced by an operation of the actuator. An example of the induced operation noise is striking noise (contact noise) occurring when the active lever comes into contact with either the wheel gear or the stopper. In contrast, the stopper formed as an elastic member, which comes into contact with the active lever, is incorporated into the device in the related art only as a countermeasure, and this countermeasure is not sufficient in fundamentally solving the problem of striking noise induced by an operation of the actuator. In contrast, in a case where countermeasures are respectively implemented for multiple striking noise-inducing regions in which striking noise is assumed to be induced, there is a problem in that a product cost is increased.